Effect of Acute Sulfur Dioxide Exposure on Bronchial Clearance in the Donkey

Abstract
The effects of 30-minute sulfur dioxide (SO2) inhalation exposures on the bronchial clearance of radioactive monodisperse ferric oxide particles were studied in three miniature donkeys. The SO2 concentrations ranged from 26 to 713 ppm. No impairment of bronchial clearance was observed at levels below 300 ppm. Higher concentrations produced severe cough and either slowing or transient arrest of bronchial clearance.